linux-kernel - Re: [v6 1/3] riscv: dts: sifive: unleashed/unmatched: Remove PWM controlled LED's active-low properties

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Message-ID: <20240116-custard-drew-9a02e83d538a@wendy>
Date: Tue, 16 Jan 2024 10:44:10 +0000
From: Conor Dooley <conor.dooley@...rochip.com>
To: Emil Renner Berthing <emil.renner.berthing@...onical.com>
CC: Nylon Chen <nylon.chen@...ive.com>, <paul.walmsley@...ive.com>,
	<palmer@...belt.com>, <conor+dt@...nel.org>,
	<krzysztof.kozlowski+dt@...aro.org>, <robh+dt@...nel.org>,
	<u.kleine-koenig@...gutronix.de>, <thierry.reding@...il.com>,
	<aou@...s.berkeley.edu>, <zong.li@...ve.com>, <vincent.chen@...ive.com>,
	<linux-pwm@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
	<linux-riscv@...ts.infradead.org>, <devicetree@...r.kernel.org>,
	<nylon7717@...il.com>
Subject: Re: [v6 1/3] riscv: dts: sifive: unleashed/unmatched: Remove PWM
 controlled LED's active-low properties

On Tue, Jan 16, 2024 at 02:20:57AM -0800, Emil Renner Berthing wrote:
> Nylon Chen wrote:
> > This removes the active-low properties of the PWM-controlled LEDs in
> > the HiFive Unmatched device tree.
> >
> > The reference is hifive-unleashed-a00.pdf[0] and hifive-unmatched-schematics-v3.pdf[1].
> >
> > Link: https://sifive.cdn.prismic.io/sifive/c52a8e32-05ce-4aaf-95c8-7bf8453f8698_hifive-unleashed-a00-schematics-1.pdf [0]
> > Link: https://sifive.cdn.prismic.io/sifive/6a06d6c0-6e66-49b5-8e9e-e68ce76f4192_hifive-unmatched-schematics-v3.pdf [1]
> >
> > Acked-by: Conor Dooley <conor.dooley@...rochip.com>
> > Reviewed-by: Conor Dooley <conor.dooley@...rochip.com>
> > Co-developed-by: Zong Li <zong.li@...ve.com>
> > Signed-off-by: Zong Li <zong.li@...ve.com>
> > Co-developed-by: Vincent Chen <vincent.chen@...ive.com>
> > Signed-off-by: Vincent Chen <vincent.chen@...ive.com>
> > Signed-off-by: Nylon Chen <nylon.chen@...ive.com>
> > ---
> >  arch/riscv/boot/dts/sifive/hifive-unleashed-a00.dts |  8 ++++----
> >  arch/riscv/boot/dts/sifive/hifive-unmatched-a00.dts | 12 ++++--------
> >  2 files changed, 8 insertions(+), 12 deletions(-)
> >
> > diff --git a/arch/riscv/boot/dts/sifive/hifive-unleashed-a00.dts b/arch/riscv/boot/dts/sifive/hifive-unleashed-a00.dts
> > index 900a50526d77..11e7ac1c54bb 100644
> > --- a/arch/riscv/boot/dts/sifive/hifive-unleashed-a00.dts
> > +++ b/arch/riscv/boot/dts/sifive/hifive-unleashed-a00.dts
> > @@ -49,7 +49,7 @@ led-controller {
> >  		compatible = "pwm-leds";
> >
> >  		led-d1 {
> > -			pwms = <&pwm0 0 7812500 PWM_POLARITY_INVERTED>;
> > +			pwms = <&pwm0 0 7812500 0>;
> >  			active-low;
> >  			color = <LED_COLOR_ID_GREEN>;
> >  			max-brightness = <255>;
> > @@ -57,7 +57,7 @@ led-d1 {
> >  		};
> >
> >  		led-d2 {
> > -			pwms = <&pwm0 1 7812500 PWM_POLARITY_INVERTED>;
> > +			pwms = <&pwm0 1 7812500 0>;
> >  			active-low;
> >  			color = <LED_COLOR_ID_GREEN>;
> >  			max-brightness = <255>;
> > @@ -65,7 +65,7 @@ led-d2 {
> >  		};
> >
> >  		led-d3 {
> > -			pwms = <&pwm0 2 7812500 PWM_POLARITY_INVERTED>;
> > +			pwms = <&pwm0 2 7812500 0>;
> >  			active-low;
> >  			color = <LED_COLOR_ID_GREEN>;
> >  			max-brightness = <255>;
> > @@ -73,7 +73,7 @@ led-d3 {
> >  		};
> >
> >  		led-d4 {
> > -			pwms = <&pwm0 3 7812500 PWM_POLARITY_INVERTED>;
> > +			pwms = <&pwm0 3 7812500 0>;
> >  			active-low;
> >  			color = <LED_COLOR_ID_GREEN>;
> >  			max-brightness = <255>;
> > diff --git a/arch/riscv/boot/dts/sifive/hifive-unmatched-a00.dts b/arch/riscv/boot/dts/sifive/hifive-unmatched-a00.dts
> > index 07387f9c135c..b328ee80693f 100644
> > --- a/arch/riscv/boot/dts/sifive/hifive-unmatched-a00.dts
> > +++ b/arch/riscv/boot/dts/sifive/hifive-unmatched-a00.dts
> > @@ -51,8 +51,7 @@ led-controller-1 {
> >  		compatible = "pwm-leds";
> >
> >  		led-d12 {
> > -			pwms = <&pwm0 0 7812500 PWM_POLARITY_INVERTED>;
> > -			active-low;
> > +			pwms = <&pwm0 0 7812500 0>;
> 
> Here you remove the active-low property, but you don't above. I'm not sure
> what's the right thing to do, but I would have expected the same change in both
> places.

Just to note, the original version of this that I acked/reviewed removed
the property from all led nodes. I then apparently didn't look closely
enough at v5 and left acked/reviewed tags on it too. It did not remove
the active-low properties but this change was not mentioned in the
changelog for the series.

D4 on the unleashed and D12 on the unmatched have the same circuitry
(modulo the placement of the series resistor) so I don't get why the
property is being removed from only D12.

I rescind my ack/review until that is clarified and/or fixed.

Thanks,
Conor.

> >  			color = <LED_COLOR_ID_GREEN>;
> >  			max-brightness = <255>;
> >  			label = "d12";
> > @@ -68,20 +67,17 @@ multi-led {
> >  			label = "d2";
> >
> >  			led-red {
> > -				pwms = <&pwm0 2 7812500 PWM_POLARITY_INVERTED>;
> > -				active-low;
> > +				pwms = <&pwm0 2 7812500 0>;
> >  				color = <LED_COLOR_ID_RED>;
> >  			};
> >
> >  			led-green {
> > -				pwms = <&pwm0 1 7812500 PWM_POLARITY_INVERTED>;
> > -				active-low;
> > +				pwms = <&pwm0 1 7812500 0>;
> >  				color = <LED_COLOR_ID_GREEN>;
> >  			};
> >
> >  			led-blue {
> > -				pwms = <&pwm0 3 7812500 PWM_POLARITY_INVERTED>;
> > -				active-low;
> > +				pwms = <&pwm0 3 7812500 0>;
> >  				color = <LED_COLOR_ID_BLUE>;
> >  			};
> >  		};
> > --
> > 2.42.0
> >
> >
> > _______________________________________________
> > linux-riscv mailing list
> > linux-riscv@...ts.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-riscv

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